Website Data Extraction via Postman

I need a Postman-only workflow that pulls user information from a site whose traffic I have confirmed runs on a REST API. The job breaks down into two parts:

• Reproduce the calls I already know about, then trace and document any additional endpoints we still need. Some are obvious from the browser’s Network panel; others may require digging into hidden XHR requests or paginated sequences.
• Assemble everything into a clean, shareable Postman collection. That collection must include all required headers, tokens, auth sequences, and environment variables so I can hit Send and receive the JSON response immediately.

Successful delivery means:
1. A Postman collection (and environment) that fetches the full set of user-data fields the site exposes.
2. A short read-me explaining where each request came from and how to refresh tokens or cookies when they expire.

No scripts, browser automation, or external code—just pure Postman. If you have handled similar REST projects—especially where some endpoints were known and others had to be reverse-engineered—tell me what you did and how long it took.